I. Field of the Invention
This invention relates generally to testing hardware. More specifically, this invention relates to a novel and improved system and method for testing communications networks.
II. Related Art
The use of code division multiple access (CDMA) modulation techniques is one of several methods for facilitating communications in systems accommodating a large number of users. Other multiple access communication system techniques, such as time division multiple access (TDMA), frequency division multiple access (FDMA) and AM modulation schemes such as amplitude companded single sideband are known in the art. However, CDMA spread spectrum modulation techniques have significant advantages over other modulation techniques for multiple access communication systems. The use of CDMA techniques in a multiple access communication system is disclosed in U.S. Pat. No. 4,901,307, which issued Feb. 13, 1990, entitled xe2x80x9cSPREAD SPECTRUM MULTIPLE ACCESS COMMUNICATION SYSTEM USING SATELLITE OR TERRESTRIAL REPEATERSxe2x80x9d, and is assigned to the assignee of the present invention, and is incorporated by reference herein in its entirety.
In U.S. Pat. No. 4,901,307, referred to above, a multiple access technique is disclosed where a large number of wireless system users each having a transceiver communicate through satellite repeaters or terrestrial base station transceivers using CDMA spread spectrum communication signals. In using CDMA communications techniques, the frequency spectrum can be reused multiple times thus permitting an increase in system user capacity. The use of CDMA techniques results in a much higher spectral efficiency than can be achieved using other multiple access techniques.
It is desirable to test the performance of the CDMA system. To determine the capacity of a CDMA system, a selected number of subscriber units or load testers may be deployed at various distances from the base station as a means of estimating the interference level corresponding to maximum system capacity. In addition to testing capacity, designers may also test air link, call processing, and network management and maintenance of the CDMA system and its subcomponents.
However, such testing may require the use of both interactive and non-interactive testing devices. An interactive device is responsive to interactive commands while, conversely, a non-interactive device is not. For example, an interactive testing device receives individual commands and acts upon them as in an IEEE-488 bus T1 line simulator. A device controlled by a C program, for example, would be non-interactive since the behavior of the device could not be changed without loading a new C program. Additionally, since various devices are used, a common device script to control all the devices required for a particular test would be convenient. What is needed is a method of using both interactive and non-interactive devices in a single test while providing a convenient single input script for all the devices used to test a system.
The invention features a system test metacontroller including an input device and a processor. The input device accepts a metascript containing commands to control devices which are part of a test arrangement. One of the devices is an interactive device responsive to interactive programming instructions and another device is non-interactive. The processor decomposes the metascript into instructions capable of driving the interactive device and the non-interactive device.
The invention is useful in simulation testing of communications networks without using actual mobile units. During the simulation, the invention permits testing using both interactive and non-interactive devices with one input metascript. In addition, the language in which the metascript is written provides a convenient testing tool. Instead of writing scripts in multiple languages for various devices, a user may write one script in a single language for all the devices used in the test.